From the Director

Rex

 

 

 

by Rex Parker, Director

Two proposals for vote at Feb 13 meeting. Last year we didn’t hold the Feb meeting because it would be on Valentine’s Day! This time around you have no such excuse (!) so we hope to see you at Peyton Hall on Feb 13. You are needed to vote on 2 proposals: (1) Amendment to the Constitution and By-Laws; (2) Expenditure authorization for a new astro video camera.

Amendment to Constitution and By-Laws. The amendment proposal is aimed at improving the organizational structure of AAAP by raising Observatory Chair and Outreach Coordinator to Board-level positions. We believe the prestige and recognition of the roles and the effectiveness of the positions would be enhanced by making them Board-level positions. They would be elected by the membership each year as are the other officers (Director, Assistant Director, Treasurer, Secretary, and Program Chair), comprising a 7 member Board of Trustees. Further rationale for this amendment is discussed in last month’s Sidereal times. The relevant sections are Constitution article 3, and By-Laws section 1. The current version is at this link, http://www.princetonastronomy.org/club_by_laws.html.

The proposed amendment also makes an additional change in the By-laws, Section 6.D.a (Finance). This would increase automatic expenditure authorization up to $500 (formerly $200) for astronomy equipment or observatory improvements at the discretion of the Officers. This is based on practicality for operating the Observatory.

Adoption of the Amendment requires a majority vote of the total membership, as provided in Article V of the Constitution.

Expenditure authorization: $2000 for astro video camera. This proposal is aimed at upgrading equipment and technology to improve observing capability for members and public outreach at the Observatory and in the field. The proposal is for $2000 from the treasury to be used to acquire a color CCD video camera and accessories for electronic assisted astronomy (EAA). To defray the cost, last month we sold some older unused astronomy equipment on Astromart, adding over $2000 to the treasury.

This Expenditure proposal must be approved by a majority of the votes cast at the meeting and not less than 30% of the paid membership, as provided in By-Laws section 6.D.c.

The club began its exploration of EAA a few years ago with the Mallincam video setup at the Observatory – with great success. More recently, EAA sessions by members at Starquest in October and at the Observatory in December demonstrated the improved sensitivity and very fast download rates of the latest generation of astro video cameras. Several models are eyepiece sized with low power requirements allowing field use with only a laptop-PC for power supply. Software has been developed allowing near-real-time color display of images on the laptop. Examples include cameras using the Sony EXview HAD CCD sensors such as the Sony ICX825. A short list of recommended cameras will be discussed at the Feb meeting.

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From the Program Chair

By Ira Polans

The February meeting will be held on the 13th at 7:30PM in Peyton Hall on the Princeton University campus.

The talk is by Paul Halpern on his book “The Quantum Labyrinth: How Richard Feynman and John Wheeler Revolutionized Time and Reality”.

From black holes and wormholes to gravitational waves and the participatory universe, this talk will show how the work of American physicists Richard Feynman and John Wheeler, who first worked together at Princeton in the early 1940s and had strikingly distinct personalities, had a major impact on contemporary science.

During the break there will be a book signing.

Prior to the meeting there will be a meet-the-speaker dinner at 6PM at Winberie’s in Palmer Square in Princeton. If you’re interested in attending please contact program@princetonastronomy.org no later than Noon on February 13.

We are still looking for volunteers to give a 10 minute talk on an astronomy related topic at a future meeting. If you’re interested in giving one in February or at a later meeting please contact me at program@princetonastronomy.org.

If you have suggestions for speakers please send them to the same email address. Please provide the speaker’s name, topic, and affiliation. Thanks!

We look forward to seeing you at the February meeting and the dinner!

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January 9, 2018 Meeting Minutes

by Victor Davis on behalf of Jim Poinsett, Secretary

Minutes of the January 2018 meeting of the Amateur Astronomers Association of Princeton

  • Director Rex Parker opened the meeting by challenging members to spot several new comets well placed for observation during January. He invited members to report their sightings—or valiant attempts—at the next meeting
  • Science writer Michael Lemonick talked about the lives and accomplishments of the Herschel family; William, his sister Caroline, and son John, based on his book “The Georgian Star: How William and Caroline Herschel Revolutionized Our Understanding of the Cosmos.” The book’s publisher did not provide copies for sale and signing at the meeting.
  • Mr. Lemonick previously spoke to the club in April, 2013 about the search for extrasolar planets, and autographed copies of his book “Mirror Earth.”
  • Member Participation
    • Rex talked about his desire to increase member involvement in club activities and encouraged members to present 10-minute demonstrations or mini-lectures to share their knowledge and experiences. He also put in a pitch for more members to use the online observatory network in which AAAP participates and has a financial stake.
  • Treasurer
    • Rex gave Treasurer Mike Mitrano a check for $2100; proceeds from selling donated equipment on Astromart.
  • Constitutional Amendment
    • At the February meeting, members will be asked to vote on a constitutional amendment to increase board membership to include the Outreach Chair and the Observatory Chair.
  • Outreach
    • Recent experiences with the Mallincam have shown the benefits of what we’ve taken to calling Electronically Assisted Astronomy (EAA). Rex proposed and members were agreeable to making additional purchases to enhance our EAA capabilities. Right now, the leading candidate is the UltraStar, and members are encouraged to conduct research and contribute opinions before a final selection is made.
    • Members discussed strategies for increasing membership, and especially for recruiting younger members to reverse the direction of our skewed demographic. John Miller suggested we need to put more effort into publicizing club activities and  capabilities to schools, newspapers, social media, community organizations, and the general public.
  • Observatory
    • Observatory Chair Dave Skitt is investigating options for motorizing the Washington Crossing observatory’s roll-off roof, a nod to the skewed demographic mentioned above.
    • Bill Murray presented an invitation to join NASA’s All-Sky Fireball Network, which involves mounting a NASA-owned camera on the observatory to observe bright meteors. The camera requires uninterrupted power and a moderately fast internet connection. After a short discussion, members agreed that hosting a camera is desirable. Bill Murray, Rex Parker, and Michael Mitrano agreed to pursue the application process.
    • Dave and Jenn Skitt and Tom Swords have removed the focuser (a formidable brass object) from the Hastings-Byrne refractor. Tom is refurbishing it (gently) for better optical alignment.

 

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Jupiter & Mars

by John Giles

I just happened to catch a SKY & TELESCOPE note on the Jupiter/Mars conjunction on January 6th and 7th. It sounded too good to pass up, so I set my alarm for 5:30 AM on the 7th to see what I could see and try to get a picture. Well, I found it turned out to be really cold! So that left out binoculars, but I’ve seen them before and thought naked eye would be OK. I was all set to drive to a good spot, but to my surprise, I could see them from my driveway, between the tree branches. What a great sight! Next project was to try to get some pictures before the camera fogged up. At -1°F, I didn’t think I had much time. I shot a few and hoped for the best.

Image by John Giles taken on January 7, 2018 at 5:50 AM from Central NJ.

Image by John Giles taken on January 7, 2018 at 5:50 AM from Central NJ.

Posted in February 2018, Sidereal Times | Tagged , , | 1 Comment

How to haul tail

by Theodore R. Frimet

baby its cold outside

Before our end of season, our Observatory Chair hosted a couple of school aged teenagers that needed to make celestial observations on a particular Friday night. Skipping ahead from the experiences of pointing out various stars, the likes of Vega, and Capella, and being somewhat dumbfounded on Polaris (sneaky North star hiding amongst the tree tops and rafters of many a barn), the student chilled to the bone, spoke out between gritted, shivering teeth, “It’s cold out here”. Welcome to Amateur Astronomy, I said.

Last night being no exception to the length of time it takes to properly prepare an amateur, we find yours truly, chilled to the toes. Experiencing unusually warm temperatures for a deep winter’s spell, and being reminiscent of our good fortune this past November, I decided to ditch the Muc-Lucs in favor of a second layer shirt, long johns, and two pairs of socks. Should have brought the Muc-Lucs. Yes, I make mistakes. Hopefully, during the course of this essay, I will fix one or few along the way. And of course, open the wounds of my personal ignorance, as I plod thru new Hypotheses, – and just like a favorite potato recipe – it may be served half-baked. I reckon that my science may not recover, as well as my toes have.

There is no undoing Newtonian classical physics, or the answer of our own respected Professional Astronomer, William Murray. When asked about the velocity relationship during the ellipse orbit of an asteroid, Bill correctly points out that as the asteroid approaches our sun, it increases in velocity. Of course what I failed to really ask Bill, is to provide me with all of my answers to unasked questions and to be a mind reader. I sobbed so quietly as I removed Sol from my sight, expecting the asteroid velocity to purr like a kitty cat in a planetary side-car. The sun persists. Gravity is real. And a gravity well reaches out to the depths of our solar system. The extremis points in the ellipses are areas of acceleration, if not in velocity, are then most certainly changes in direction.

Our asteroid travels in an ellipse and gains momentum on each pass around the sun. Hmmmmm…not unlike the lore of science fiction shows where our space travelers must hurl their craft around the sun to gain needed momentum to make it to Jupiter in a few less months than strategically laid out at the beginning of their fare – our NEO’s are forever gaining speed. Going faster, and faster and eventually reaching, “terminal” escape velocity. Emboldened with the momentum to breach the gravity well of Sol, they faithfully return to the OORT cloud for further dispensation of plans divulged by the sky gods of old. That is unless they don’t have the mass necessary to escape despite the increase in their velocity bank account.

Having some more amateur fun, here, run the clock backwards and decrease the velocity on each pass, to approximate the entry speed of this heavenly body. You’d have to wait awhile for this months eyeful to rewind on my pretentious timepiece. As she punches her time clock, to be on the job, only every 20,000 years. Enter C/2016 R2.

You can jump to the bottom of the essay, or suck it up, put on that 80 lb rucksack soldier, and tramp up that 30 degree incline in the wastelands of the desert. You decide. As there is no return once you enter the next paragraph.

You can’t fix stupid? Sure you can. Be patient, and get thru all of the long reptilian length sentences until you strike gold. Ah, you are still here? Good. Then I hand you the olive branch of tangential velocity to correct last months poor mans calculation of linear velocity.

Working side by side with a lab paper from “A Manual to Accompany Software for the Introductory Astronomy Lab Exercise Edited by Lucy Kulbago, John Carroll University 11/24/2008” I hurriedly excerpt some bits and tidbits to reach another conclusion as to how fast asteroid 1362 Griqua was moving in last months video.

First let’s calculate the angular velocity. I tried avoiding this last month – as this explains why I invented Griqua units of measurement. Alas, the truth be known. You and I must brave the winter of our discontent and move on to newer, richer pastures and relish in the truth that will bear us out in the end – a method and a resulting number that is closer to reality.

So that I do not get lost in the labyrinth of my own observations, I am noting here that Skynet 1362 Griqua observation # is 2335994, and the ID and location of image 0 and image 7 are:
ID: 19892011 RA/DEC: 00:27:52.198 / -24:59:39.468
ID 19892018 RA/DEC: 00:27:54.559 / -24:59:11.705

Both imaged on Prompt-5 telescope employing a Lum filter, and 4 seconds exposure.

The Universal Time (UT) stamp on my first image (image 0) is 01:30:06.154, and on my last (image 7) is 02:06:53.926. Whew! That was a mouthful !

We convert the hours, and minutes to seconds to make the math easier, multiplying minutes by 60 and hours by 3600.

01:30:06.154 = 5,406.154 s
02:06:53.926 = 7,613.926 s

Now take the difference, which will result in the time that passed between observations of image (0) and image (7) at the telescope: 7,613.926 – 5,406.154 = 2,207.772 s

The time elapsed was 2,207.772 seconds !

That was some pretty basic arithmetic. Now we have to delve a little deeper into the frugal realm of Pythagoras.

c (squared) = a(squared) + b(squared)

Or if you will permit me to flaunt my limited mathematical prowess:

c = the square root of ( (a*a) + (b*b) )

Hurray for right ascension and declination. They are the known coordinates of where we looked into the night sky. They happen to have a happy relationship as right angles to each other.

If you would, “one goes up” while “the other goes down”. No? How about, “right ascension or RA” is like horizontal direction, and “declination or DEC” is our vertical direction?

Still no?,…ummm..ok – my bad – I’ll try again – RA and DEC are two legs of a right triangle and we are going to solve for the hypotenuse. Yup, sorry. You asked teacher back in high school, “what am I going to do with geometry?” – well, here it is, my fellow budding amateur.

Take the DEC values, from above, and convert the coordinates to arc seconds. Multiply the minutes by 60 and the degrees by 3600. Sounds familiar, doesn’t it?

24:59:39.469 = 89,979.469 arc seconds
24:59:11.705 = 89,951.705 arc seconds

Now take the difference to find the change in DEC for our images:
89,979.469 – 89,951.705 = 27.764 arc sec

Take the RA values, from above, and convert the coordinates to seconds. Again, multiply the minutes by 60 and the hours by 3600.

00:27:54.559 = 1,674.559 seconds
00:27:52.198 = 1,672.198 seconds

Now, take the difference to find the change in RA for our images:
1674.559 – 1,672.198 = 2.361 sec

Our noteworthy author points out that our RA system is a grid of bent lines from earth bound pole to pole. And that the closer to the poles, the less space between the lines. And the closer to the equator, the more space between the lines. This curvature issue is solved by introducing the cosine into our math.

Another way to look at this, is that the circles that circumscribe the earth, as we vary the latitude, get smaller and smaller as we work our way to either North or South pole. That is what the cosine is there for.

First convert the DEC to degrees by dividing the arc seconds by 3600:
27.764 / 3600 = 0.00771222 degrees

change in RA(adjusted) in arc-seconds = RA in seconds X 15 X cosine(DEC in degrees)

[note: the declination in degrees is NOT the difference, it is the actual DEC rounded off to the nearest degree]

= 2.361 X 15 X cosine(-25)

Pray tell – where doeth the “15” come about, you query?
Tarry you not the Ides of March, as they dare not wary you!

Quoting the Astrometry Bard, straight out of the student manual, p5:
“This may sound strange, but an hour of right ascension is defined as 1/24 of a circle, so an hour of right ascension is equal to 15 degrees.”

Well, not so strange to us, is it? Amateurs know that RA is measured in hours, minutes and seconds conforms neatly to the idea of our Earthly rotation.
i.e., 1 x hr = 15 deg, 2 x hr = 30 deg, 3 x hr = 45 deg, …, 24 hr = 360 deg.

= 2.361 X 15 X cosine (-25)
= 2.361 X 15 X (0.9063)
= 32.097

Back to old Pythagoras:

take the square root of:
(32.097 * 32.097) + (27.764 * 27.764)

(1030.210) + (770.840) = 1801.050

= 42.439 arc seconds

Calculating the angular velocity of asteroid Griqua on December 27, 2017 is:

=42.439 / 2207.772 seconds
= 0.019 arc seconds / second

( yes-sir-ree Bob! that be “arc seconds” per “second” ! )

Now onto the clear blue waters of Tangential Velocity of my beloved Griqua.

We need to know its angular velocity (already calculated as above), and its distance. Since I have no parallax data to provide us with (which would be used to calculate distance to the asteroid) we will peer into one of NASA’s databases to find our distance, on the evening of December 27, 2017, and use the starting time of observation for our starting point in time. However, as we look into a National solution, we find none. So we expand our search to include those found across the pond.

Plugging in our date time group, for our first and last observation into the ephemerides generator, located at the AstDyS-2 sponsored by ESA, and being observant to enter the telescopes’ location at Cerro Tololo, observatory code: 807, I get a delta (distance to asteroid from Earth) that varies from 1.9204 astronomical units (AU) to 1.9206 AU. Let’s use 1.9205, shall we? Lets take a look at the ephemerides data here.

According to a Wikipedia article, last referenced on Wednesday, January 24, 2018 at 16:46 PM EST, the definition of an Astronomical Unit (AU) has been defined exactly as 149597870700 meters, since 2007.

1 AU = 149,600,000 km
1.9205 AU * 149,600,000 = 287,306,800 km

Tangential Velocity = (Angular velocity X distance) / 206,265
Vt = (0.019 X 287,306,800 / 206,265

Vt = 26.5 km/s

Applause, if you please!

Now, fair warning, dear amateur. There is no rest for the weary. And the faint of heart need not travel the road less taken. You may skip the EPILOGUE and feast your eyes on the tantalizing video of a blue tailed comet, as linked at the end of this essay as my timeless gift to you!

EPILOGUE:

Here is a tad of math, that fellow UACNJ member Eric Leonard schooled me on. As an aside to correcting mistakes in units, above, Eric was singularly responsible from rescuing me from my inability to reconcile finite mathematics and integrating my renewed awareness of the celestial sphere into real geometric examples.

Where I shamelessly plodded along and entered values into formulae, Eric was tireless in his approach in making rock solid certain that I walked away from this enterprise, knowing my DEC from my RA.

For more on Eric Leonard, please subscribe to Eric’s “Math From The Gut” videos series on Test Driving Pythagorean Theorem.

Now, let’s visit below, to be rock solid on where the number “206,265” comes from.

First off, let’s state the following, that 206,265 is equal to (360 * 3600) / (2 PI)

In the above statement, 360 is in degrees, and 3600 is in arc seconds per degree, and where 2 PI is the value of a unit circle.

360 degrees * 60 = the number of arc minutes that go around the circle.
360 degrees * 3600 = the number of arc seconds that go around the circle.
one arc second = 1/(360 degrees * 3600)

The relationship of the distance around the unit circle to its degree measurement is as follows:

2 PI km / (360 degrees * 3600 arc seconds/degree)

Inverse the above, plodding our relationship into the denominator:

1 / (360 degrees * 3600 arc seconds /degree) / 2 PI km

Which brings us to rekindling the tangential velocity equation, first found on p25, of the Student Lab Manual, Astrometry of Asteroids, cited earlier in this essay:

Vt = (angular velocity x distance)
—————————————————————
(360 degrees * 3600 arc seconds / degree) / 2 PI km

In the above equation, briefly study the denominator. In its construct, the denominator’s “numerator” holds our number of arc seconds in a circle. And in the denominator we have 2 PI, which is the diameter of a unit circle. Above the “big line”, we will find our angular velocity multiplied by the distance to the asteroid (measurement courtesy ESA ephemerides).

Let’s revisit the equation with a slightly improved understanding of the “206,265” origins.

Still not on board with 206,265 ?
As a quick reprise, here is the brute math of it: [360 * 3600 / 2PI = 206265].

Velocity = (Angular velocity X distance) / 206,265

Let’s do our math a little differently, here (holding off on the distance value, for just for a bit!)

Divide the Angular velocity by 206265 which yields:
v = 0.0000000921 km / s on a unit circle

Generically speaking, we can state an “x” value for km/s, as found below:
(x km /s along a unit circle) * 287,306,800 km / 1 km

And for clarity, re-write it with the “big line” of division, here:

(x km / along unit circle /s ) * (287,306,800 km along comet circle)
———————————————————————————————————————————
1 km along unit circle

Substituting our previous result (v = 0.0000000921 km/s on a unit circle) for the “x km/along unit circle/s), we show the math as found below:

Vt =

(0.0000000921 km/s along a unit circle * 287,306,800 km along comet circle
————————————————————————————————————————————
1 km along unit circle

Vt = (0.0000000921 km/s ) * (287,306,800 along comet circle)
Vt= 26.5 km/s along comet circle

I have restated the equation, below, with correct unit notation, and all with the help and timeless assistance of Eric Leonard.

Vt = (0.019 arc seconds / second x 287,306,800 km) / 206,265 arc seconds / km along a unit circle

Vt = 26.5 km/s

Note: since “arc seconds / second” has the unit “seconds” in the denominator
and “arc seconds / km” has Km as 1/km as in it is in the denominator
then it follows that after we cancel out units, we are left with: km/s

Having already done the “walk of shame” on my 1362 Griqua video, you can note, here, and there that I’ve researched velocity of record as follows:

I used Google translator on the below website link – a German wikipedia. It records the velocity of 1632 Griqua having an average orbital velocity of 16.59 km / s. Which would be a much higher velocity than I have reported in this video. Here is the link to the translation (Sunday, December 31, 2017 9:40 AM EST)

A Russian wiki records the velocity of 1362 Griqua at 16.016 km/s. Here is a link to this translation (Sunday, December 31, 2017 10:03 AM EST):

So, bearing in mind the calculations that have preceded us, according to German and Russian Wiki records, their 16.59 – 16.01 km/s is pretty darn close to our calculation, as performed by this amateurs essay of 26.5 km/s. And is astounding more precise than the “Griqua units” of lore which previously resulted in faux calculation of 430 km/hr.

Let us ballpark our numbers of precise mathematical measurement of 26.5 km/s and either way you rate it, Griqua was hauling tail thru our neck of the solar system – just the other day – astronomically speaking, that is.

You’ve struggled with the math. And slugged it thru my stream of consciousness writing style. And for all of that effort, may I bestow a token of my appreciation upon you:

a blue comet.

Enjoy!

P.S. – Skynet, the Robotic Telescope Network, hosted by UNC Chapel Hill, under study by many of our club members, permits us the opportunity to employ multiple telescopes located around the world. And perhaps, given the chance opportunity to revisit parallax, for a home grown distance calculation by observation, we can schedule two or more telescopes to observe the same NEO, in space and in time. I look forward to your participation and contributions, thru Skynet, or the clubs forthcoming acquisition of Electronically Assisted Astronomy (EAA), or your home observatories. Thank you for reading, -Ted

ἐπίλογος – Cassius:

“The fault, dear Brutus, is not in our stars,
But in ourselves, that we are underlings.”

(Julius Caesar, Act I, Scene III, L. 140-141).

We are not trying to stop a monarch of Rome. The sense of it is that many score years will pass us all by. Then, a youngster gives a fleeting thought to how fast an asteroid travels thru space.

We have given this future amateur astronomer, our pause, our here and now…and paid the purse with mental coin, emerging with a few neural pathways intact.

Here lay your underling. I am yours truly. I have beaten a plowshare back into a sword and cleared a minor path to “brute” understanding of a minor planet’s tangential velocity calculation.

If it be not accurate, perhaps we can put it safely to bed, in the knowledge that it is, at its core, more precise than a “Griqua” guess.

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Comet 2016 R2 (PANSTARRS)

by Rex Parker

A group of AAAP members met at the Observatory Jan 19 to seek comet 2016 R2 with the Mallincam/5″refractor. They succeeded in this challenge – which took some skill as the comet was very faint, TheSkyX reporting magnitude 13.2 as the comet receded away from earth and sun (well past it’s peak brightness). I was not able to attend that observing session but was able to get an image of the comet on the same night locally, using a 12.5″ telescope and CCD camera at home.

The comet picture below is assembled from 6 x 2 min exposures in each color filter (L,R,G,B) taken at intervals over 40 min. By tracking using the comet’s orbital elements rather than sidereal rate tracking, the comet is stationary in the composite image while the field stars trail. Just the faintest hint of a dispersed comet tail might be seen in the image going to the right from the head.

Comet 2016 R2 from central NJ on Jan 13 at magnitude ~13.2. Image by RAParker.

Comet 2016 R2 from central NJ on Jan 13 at magnitude ~13.2. Image by Rex A. Parker.


This image gives a different look to the comet compared to the technique used by member Ted Frimet using Skynet, who took shorter images at intervals using Skynet with the mount tracking the stars, revealing the comet’s motion against the steady background stars when displayed as video.

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Black Holes

by Prasad Ganti

An episode of Nova titled “Black Holes” was aired recently on PBS (pbs.org). The latest issue of Scientific American carried an article by Priyamvada Natarajan on the same subject. The author was also featured on the Nova program. While the Nova program started off with the black holes as a prediction of Albert Einstein’s theory of General Relativity from the early 1900s to the present day discoveries, the Scientific American article focuses only on the recent discoveries.

Albert Einstein came up with the general theory of relativity in 1915 to describe the effect of gravity on space and time. Karl Schwarzschild, the Jewish Physicist and an Astronomer fighting for Germany in World War I, solved Einstein’s equations and came up with the concept of an object of immense mass packed into a very small volume, which warps the space and time so much that even light cannot escape once it is trapped. It remained a concept for several decades. Schwarzschild died immediately after the war due to a disease he had contracted on the war front.

Lot of debate ensued as to the existence of black holes and the process of trying to find them. Any object cannot be a black hole. Schwarzschild had come up with a radius for a given mass. Unless the mass is packed in a very small radius (for those who are mathematically inclined, R=2*G*M/c**2, G is the gravitational constant, M is the mass of the object, c is the speed of light). Since the speed of light is huge and occurs in the denominator of the equation and gets squared, the radius is very small indeed.

While the black hole itself will only devour mass and not give out anything, its surrounding halo can emit radiation. The gas and dust swirling around the Black Hole gets heated to very high temperatures, giving off radiation. X-rays were observed in 1964 to be coming out of a source in Cygnus constellation. Speculation arose that there could be a Black Hole resulting from the collapse of the corresponding star. Betting took place between Stephen Hawking, the famous contemporary astronomer and Kip Thorne the Nobel prize winner from 2016. Hawking was skeptical that the X-ray source was a black hole. Thorne finally won the bet in 1990 when data overwhelmingly conferred the honor of the first black hole to be discovered on Cygnus X-1.

Such black holes which form from the death of a massive star are known as stellar black hole. Stars need to be much heavier (several times at least) than our Sun to die and result in a black hole. There was a growing evidence of a massive black hole in the center of our Milky Way galaxy. Other analysis of hundreds and thousands of galaxies revealed supermassive black holes in their centers. They grow by accumulating dying stars in the galaxy like a big corporation forming from the mergers and acquisitions of smaller companies!

In the 1960s, very bright but distant objects were found. Christened as Quasars (Quasi Stellar Radio Sources), these objects were the brightest ones found to date in our universe. But being the furthest objects to be discovered, quasars were mysterious. What powered their luminosity? They are certainly not massive stars. Since looking far away in universe always means looking back into the past, quasars are the oldest objects in the universe, formed when the universe was still in its infancy.

Now it is agreed that quasars are powered by black holes. But how did black holes form in such early stages of the universe. Stars were just forming, so there could not be corpses of stars. Latest theory is that huge masses of cloud and dust directly collapsed into black holes, instead of going through the star formation process.

Black holes keep devouring matter in their neighborhood. They grow in size. Mergers of black holes and other dense objects produce gravitational waves, which have been detected in the last couple of years. With the launch of James Webb space telescope in 2019, more is expected to be known about quasar formation. Astronomy is getting more exciting with these discoveries and there is endless potential for more. Our universe is a very interesting place indeed!

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Snippets

compiled by Arlene & David Kaplan

- SpaceX

– SpaceX

The biggest space missions in 2018
Next year is already overflowing with exciting missions to space. NASA is launching a new lander to Mars, as well as a spacecraft that will get closer to the Sun than ever before. And two of NASA’s vehicles already in space will finally arrive at their intended targets…more

Tiangong 1's path - Aerospace Corporation

Tiangong 1’s path – Aerospace Corporation

A Space Station Is Expected to Fall Out of the Sky
Sometime around the start of spring, a 9.4-ton Chinese space station is expected to come hurtling back to earth.
The space station, Tiangong 1, is predicted to make that return trip in mid-March, give or take a few weeks, according to an analysis by the Aerospace Corporation, a federally funded research and development center in California. But don’t worry: Odds are no one will be hurt…more

Universe’s oldest known galaxies – NASA

Hubble scores unique close-up view of distant galaxy
Astronomers were lucky when the orbiting observatory captured the image of a galaxy that existed just 500 million years after the Big Bang. The image was stretched and amplified by the natural phenomenon of gravitational lensing, unlocking unprecedented detail. Such objects usually appear as tiny red spots to powerful telescopes…more

UK satellite to make movies from space

UK satellite to make movies from space

UK satellite to make movies from space
A British satellite has gone into orbit on an Indian rocket to acquire full-colour, high-definition video of the surface of the Earth. The demonstrator is expected to pave the way for a series of at least 15 such spacecraft, which will be operated by the Guildford-based company Earth-i…more

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